I have a router so i forwarded my ports using the automatic port forwarding software PFConfig and after made a CSS dedicated server. I tried to connect to my server using external IP and it worked! Which was great for me to be honest because it is first time i got it working, as before i did not know how to make server having router. The problem is that when i joined, after about 30-40 seconds the game lagged and I had connection problem error. I've looked in the console and it said as Server timed out. Fine i quit the game and i thought that the server would be off but it was on and working properly, in console of server it said that Player Ren has timed out or smt like that. I tried to join the server again and it doesnt work on second time, i have to restart the server to join again. But it keep doing the same thing all the time. Maybe some people who have hosted a CSS server know how to solve this problem? I dont want the server to be public and running 32 people on it, i just want to make it stable so i can set it up and play with my friends on weekends. Thanks.
You say you connected to it through an external IP? Are you running on the same LAN as the server? Could be a weird issue with your router connecting through itself. Got any friends to test it out on?